Southeast Asia forum

Hi all,
My boyfriend and I are planning a 6 week trip through Vietnam, Cambodia, Laos and Thailand from mid-Jan through Feb and I'd love some feedback on our itinerary. To save time, we are probably going to do the Airpass through Bangkok Air and fly Siem Reap - Vientiane , Luang Prabang -Chiang Mai and Chiang Mai-Bangkok. I've been doing a lot of research and reading on various websites and guidebooks and these forums have been invaluable, so thanks in advance for any advice. Here's our plan:

1/20 - arrive HCMC
1/21-1/23 - HCMC
1/24-1/26 - Mekong Delta (think we will DIY it via Vinh Long, Can Tho, Chao Doc and boat to Phnom Penh )
1/27-1/28 - Phnom Penh
1/29-1/31 - Siem Reap (via Mekong Express)
2/1-2/3 - Vientiane
2/4 - bus to Vang Vieng
2/5-2/6 - Vang Vieng
2/7 - bus to Luang Prabang
2/8-2/12 - Luang Prabang
2/13 - fly to Chiang Mai
2/14-2/19 - Chiang Mai
2/20 - fly to Bangkok
2/21-2/22 - Bangkok
2/23-2/25 - beach??
2/26 - fly home

As you can see, we're spending a good chunk of time in Luang Prabang and Chiang Mai, as those are the places that most interest us and will hopefully serve as a good base for a trekking trip or 2.

My questions are these:

-We are still debating whether to go to Vang Vieng/Vientiane. Not too keen on the whole drunken white people scene but are we missing out on beautiful scenery? Also, would we be missing out on a lot by skipping Vientiane? We'd probably spend more time in Luang Prabang and Phnom Penh if we cut those out.

-Still debating how to visit Mekong Delta. Don't want to do the cattle call tours but can't afford to pay $250+ for a smaller tour. We were thinking of DIY-ing but since it's at the beginning of our trip we're thinking it might be nice to have someone else thinking about logistics etc. Advice? Tour recommendations?

-We're thinking of spending the last few days relaxing on a beach somewhere before flying out--any recommendations for some low-key spots (read: not a party scene, beautiful, cheap) within a few hours train or bus ride from Bangkok? Ideally we'd go there for a few days and come directly back to Bangkok airport to fly out without having to spend the night there--our flight is an afternoon one--so something close is essential.

Thanks for reading and excuse the long-windedness--lots of planning has made my head foggy!

cheers,
*rebecca